have one's back up

• Audio (AU)

  (file)

have one's back up (third-person singular simple present has one's back up, present participle having one's back up, simple past and past participle had one's back up)

1. (idiomatic) To be angry or defensive.

   He's had his back up all morning. There's no point in trying to talk to him.

• get one's dander up, get one's Irish up

• put someone's back up
• raise someone's hackles
• ruffle some feathers
• get someone's back up